I do a lot of volume mounting. To make it easier, and quicker, I print with a one inch border around the print, and cut the window to expose 1/2 inch, of the paper border. I dry mount them. They are then bagged, to keep them clean.
For other, unmounted prints, I store them in archival boxes.

If you're planning on doing a lot of this, it's worth investing in a good mat cutter, with production stops, and buying mat board in 32x40 inch size. The windows you cut from a large print can be re-squared and used for smaller mats. Quality board is expensive, and this will give you the most bang for your buck.